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Tuesday, June 17, 2014

The two houses of Congress have written their proposed 2015 budgets for
NASA. The House bill would add
additional funding to almost every category of the Planetary Science budget and
would greatly strengthen NASA’s program of planetary exploration. The Senate bill would add substantial funds
to the Mars program but pay for this by cuts to other portions of the planetary
budget.

In American politics, the President proposes federal budgets but it is
Congress that decides federal budgets.
Last winter, the President’s budget office proposed a Fiscal Year 2015
planetary budget that was better than proposals for previous years but still
well below the levels needed to enact the program laid out by the science
community in the Decadal Survey. Both
houses of Congress have now proposed their alternative plans (although the
Senate budget has not been approved by the entire body yet). How has planetary exploration faired?

It’s useful to start by looking at their changes to NASA’s entire
science program. Each of the science
divisions – planetary, astrophysics, heliophysics, and Earth – are operating on
budgets well below what’s needed to fulfill the visions in their Decadal Surveys. However, the political parties have settled
on a budget compromise that sets a limit on overall government spending. Within that limit, the Congressional bills
have been fairly generous in proposing increases for NASA’s science programs in
lieu of spending on other government programs.
Both Congressional bills would increase funding for astrophysics, but
the House favors a substantial increase for planetary exploration while the
Senate proposes a modest increase for Earth science (most of which is simply
the transfer of satellite programs and their funding from another government
agency).

Within the proposed budget for Planetary Science, both bills propose to
increase funding to the Discovery program to enable these small missions to be
flown more frequently.The bills differ
substantially though in whether they favor a substantial increase to the Mars
program (the Senate) or for defining a Europa mission through increased Outer
Planets funding (the House) and to the research and analysis and technology
development programs (the House).Both
bills appear to provide funding sufficient to operate all missions already in
flight, reversing the proposal in the President’s budget to shut down the Mars
Opportunity rover and the Lunar Reconnaissance orbiter.(The Senate bill does not directly address
the latter but does appear to provide sufficient funds for the orbiter.)

Both the House and the Senate bills propose to increase spending for
the Mars program.The House bill would
add $22.7M, a bit more than is needed to continue operating the Opportunity
rover as well as all other Mars missions in progress and continue the development
of the 2020 Mars rover.The Senate bill
would be much more generous with an increase of $65.7M.The Senate bill specifically states that it
wants to see all current Mars missions continue operating (which would require
approximately $15M over the President’s request) but does not specify what the
remainder of the funding would go towards.NASA could use the remaining increase for development of the 2020 Mars
rover, which is on a tight budget.

Both the House and the Senate bills would provide increased funding for
the Discovery program with the increase targeted to enabling selection of the
14th mission in the series to occur in approximately two years. (The 12th missions, the Mars
InSight geophysical rover is in development and is fully funded, and the
selection process for the 13th mission is in progress.) Both Congressional bills direct that Discovery
missions are to be selected every two years in accordance with the
recommendations of the Decadal Survey rather than the every five years of the
past decade.

If the Discovery program receives funding in future years’ budgets for
missions every two years, or five per decade, this is a tremendous boost to
NASA’s program.

Both Congressional bills state the importance of a mission to globally
explore Europa, but take very different directions with recommended funding
levels. The House bill would add $85.3M
to the Outer Planets budget, which on top of the President’s request would
provide $100M to continue preparatory design for the mission. The House bill directs NASA not to consider
any Europa mission that would be substantially cheaper than the ~$2B Europa
Clipper it is currently defining. This
is in response to the request of the President’s budget office and NASA senior
management seeking ideas for a mission that would cost approximately half as
much. The House bill states that the
committee that drafted its bill has not seen any “credible evidence” that a
scientifically useful mission could be flown for $1B.

The Senate bill cuts the Outer Planets program by $16.7M, or a little
more than $15M the President requested for Europa studies. (The remaining funds would support the
Cassini mission at Saturn and pay for development of US instruments on the
European JUICE Jupiter-Ganymede mission.)
The Senate bill gives no explanation for the cut. In fact, it states in the text that it
support’s the President’s funding levels for the Planetary Science program except
for increases the Discovery and Mars programs.
The cut to the Outer Planets funding appears in a table, but no
explanation is given.

The Senate bill directs NASA to plan to use the Space Launch System
(SLS) booster to launch a Europa mission, while the House directs NASA to
consider using the booster. The SLS has
the ability to deliver a Europa mission to Jupiter in around 2.7 years compared
to a 6.4 year transit if commercial boosters are used. However an SLS launch would cost ~$1B
compared to a few hundred million dollars for a commercial launch. Congress plans to fund the development and
building of several SLS boosters so their cost is already covered.

While the House and Senate bills both would increase net spending to
develop future missions with one favoring Mars and the other Europa, the Senate
bill would cause harm elsewhere. While
the House bill supports small increases to the Planetary Science program’s
research and technology programs, the Senate bill would impose significant cuts
to these programs. Cutting the research
program likely would reduce grants to scientists. At best, this would stall work to analyze
data returned from NASA’s missions. At
worst, this would force a number of scientists and graduate students who depend
on these grants to leave the field.

Eventually, the two bills will be reconciled into a single budget that
will set NASA’s funding for current and future missions for 2015. From my news reading, it’s widely expected
that the final reconciliation of the House and Senate budgets won’t occur until
late this year following the Congressional elections in early November.

Thursday, June 5, 2014

NASA’s Mars Exploration Analysis Group (MEPAG) recently reviewed plans
by Europe, the Japanese, and the U.S. for future Mars exploration. The prognosis is for another kick ass decade
of Mars exploration.

We have enjoyed two decades of increasingly more focused exploration of
Mars. After a lull of twenty years, the 1996
Mars Pathfinder lander began what has became a flotilla of orbiters, landers,
and rovers to examine the Red Planet in increasing detail. Missions in flight or in development will
explore the processes that are stripping away the atmosphere, measure its trace
gases, and study the interior of another planet for the first time. Two missions will land rovers to poke and
prod two locations in detail. This is in
addition to the three orbiters and two rovers currently exploring this
world. Only for our moon do we have such
a rich understanding of another world.

The MEPAG meeting last month included the usual program review, but it
also coincided with the second workshop in the long selection process for the
landing site for NASA’s 2020 rover mission.
In this post, I’ll share highlights from the two meetings. (You can read the presentations here.)

Credit: J. Green, NASA

The European Space Agency (ESA) has an active Mars program with the
Mars Express orbiter currently at Mars, two ExoMars missions in development,
and planning under way to select follow on missions. It will jointly develop and fly the two ExoMars
missions with the Russian space agency Roscosmos. The first, set to launch in 2016, will have
an orbiter that will focus on atmospheric chemistry and dynamics along with a
small European technology demonstration lander.
The second, to launch in 2018, will deliver a highly capable rover and
station that will search for signs of past or present life.

The current tensions between the US and Russia over the Ukraine have
the potential for disrupting these missions.
NASA plans to deliver its Electra communications package for the 2016
orbiter that will allow it to relay data from surface landers and rovers back
to Earth. Both ESA’s 2018 ExoMars rover
and NASA’s 2020 rover missions plan to use the ESA orbiter to relay data back
to Earth. Because Russia will launch the
mission, shipping equipment to Russia with the current political tensions over
Ukraine may prove difficult. With launch
just two years away, there’s little time to recover from any delays if they
occur. NASA also plans to deliver a key
parts of one of the 2018 rover’s instruments, but there is more time to deal
with that issue.

Other highlights from the ESA presentations:

Both the 2016 and
2018 missions are on track other than the potential export issue (although no
mention was made of whether or not funding has been fully secured for the 2018
mission which has been an open question).

Russia is still
scheduled to provide the key entry, descent, and landing system for the 2018
rover. This will be a major project for
a space agency that hasn’t had a successful planetary mission in decades.

Russia plans to
host a surface station in the 2018 lander platform for long-term studies of the
atmosphere and geophysics of Mars.
Instrument selection will begin this spring.

ESA is considering
three missions to follow the 2018 rover.
The current favorite, Phootprint, which might launch in 2024, would be a
possible third joint mission with Russia and would return a sample from the
Martian moon Phobos. Other options would
be for three small geophysical landers to establish a network to study Mars
interior or a small rover to explore a new region of Mars.

Japan’s space agency, JAXA, is considering several mission options for
a future Mars mission, but has no currently approved Mars missions. (It’s only previous attempt to reach Mars,
the NOZOMI orbiter, failed.) For its
next try, JAXA’s managers are considering several small missions including an
engineering demonstration to use the atmosphere to slow the spacecraft to enter
orbit (aerocapture), an airplane to survey magnetic anomalies this will provide
clues on Mars’ ancient but now defunct magnetic field, and a meteorological
station or seismic station. The
presenter, however, spent the most time describing the most ambitious concept,
a rover that would be smaller than the Opportunity rover at ~60 kilograms. Two goals for the rover were described in
some depth – an environmental package to study dust movement by the atmosphere
(including dust devils) and a relatively simple microscope that would use
fluorescence to detect biosignatures in the soil. Launch would be sometime in the 2020s.

A presentation on the NASA MAVEN mission that will study loss of the
atmosphere into space gave the good news that all is well with the craft. It arrives at Mars on September 21st
this year.

The Europeans and Russians will not have the only mission to Mars in
2016. NASA’s InSight geophysics station
will launch that year to study the interior of Mars. The lander also will carry a capable weather
station to enable scientists to determine the influence of temperature and
winds on its measurements. The InSight mission
has always planned to carry a camera to aid in instrument deployment, with one
panorama planned early in the mission.
The project will attempt to replace the currently planned black and
white camera with a color camera, but there are no promises. The mission development is proceeding well
and the team has received permission to start hardware development following an
in-depth review of the design.

The focus for the two meetings, though, was NASA’s 2020 rover. Like the Curiosity rover currently on Mars,
the 2020 rover will pursue the question of whether Mars could have hosted life
in the past (or even in the present). While the Curiosity rover does that only with
the scientific instruments it carried to Mars, the 2020 rover also will select
and cache 25+ rock and soil samples that could be returned to Earth for study
with much more sensitive instruments in terrestrial laboratories.

Credit: B. Ehlmann, JPL/Caltech

In addition to exploring a site in terms of its past habitability, a well chosen site could also allow studies related to the key questions for Mars identified by the Decadal Survey that set priorities for solar system exploration. The 'Noachian' era was the earliest on Mars when abundant surface water may have created conditions suitable for life. Credit: B. Ehlmann, JPL/Caltech

NASA plans to build and fly the 2020 mission for just half the cost of
the Curiosity mission, adjusted for expected inflation. The need to collect samples and control costs
will ripple through portions of the mission plans. (An additional new goal, to gather
measurements and test hardware that would be useful to a future human mission
will also drive some changes.)

One portion of the mission that will be familiar will be the design of
the rover and the hardware that delivers it to Mars. NASA believes that up to 90% of the Curiosity
mission’s design (by mass) can be reused (which enables a highly capable
mission at bargain price). Some changes
will fulfill the new mission requirements (for example, the caching hardware)
and others will apply lessons gained in operating Curiosity (for example,
beefier wheels after Curiosity’s showed unexpected early wear).

The instrument suite the 2020 rover will carry is likely to be substantially
different than Curiosity’s. Curiosity
carries instruments that both can make quick measurements to rapidly assess the
geology of a location and a highly capable laboratory that can make detailed
measurements. The latter, though, is
costly both in dollars and in the time needed to make the measurements. In almost two years of operation, Curiosity
has collected just three samples for its laboratory instruments. In that same time for the 2020 mission,
scientists want to fill most or all of their cache. As a result, the 2020 rover may carry only
rapid assessment instruments in addition to its caching system (although
technology advances may mean that some will be much more capable than their
Curiosity equivalents). NASA is
expected to announce the instrument selection this July.

The desire to cache samples also is leading scientists to prize the
diversity in evaluating landing sites. Scientists
want its samples to represent the broadest range of ancient environments and
processes as possible. While almost half
of the Martian crust is older than 3.7 billion years when life might have
formed (compared to less than 1% for the Earth), many of those locations would
provide limited diversity within the range a rover could explore. (Many also would be unsafe to land at.)

The NE Syrtis Major site (second from the bottom) has a wide range of diversity. This chart is a draft and may change as the diversity of other sites is further assessed. Credit: B. Ehlmann, JPL/Caltech

At the end of the landing site workshop, the participants held a straw
vote to indicate which sites they found most compelling. The winner, located on the northeast edge of the
plains of Syrtis Major, illustrates the diversity they would like to find. Within a few kilometers, this site provides
access to samples that record key stages of Mars’ early evolution:

Blocks of rocks
hurled from nearby massive impacts record the early bombardment of the
terrestrial planets by comets and asteroids.
These are also convenient samples of the ancient crust delivered from
outside the landing zone.

Ancient crust with minerals
preserving the record of the early wet environments of Mars that may have provided
conditions for life to develop or at least that record biotic precursors. The NE Syrtis Major site has an unusually wide
range of aqueous minerals that suggest a diversity of environments that came
and went across millions of years as the climate dried out.

A nearby volcanic flow
represents the massive volcanism that covered large areas of the planet in its
early history. These rocks could record
the chemistry of Mars’ ancient mantle, provide clues on when Mars’ ancient
magnetic field shut down, and in terrestrial laboratories provide unambiguous
dating of a wide-scale event to calibrate dating of Mars’ early history.

The proposed NE Syrtis Major landing site includes geologic formations from the two most ancient eras on Mars, the Noachian and the Hesperian. The site has remnants from ancient impacts, several types of aqueous minerals, and access to volcanic rock formations. Credit: J. Mustard, Brown University

At this point, NASA is not looking to rule out any of the nearly thirty
sites that have been proposed. While the
NE Syrtis Major site won the initial beauty contest, other sites may prove to
be more desirable with further analysis.

While NASA doesn’t need to select the 2002 mission’s landing site until
2019, two factors are pushing it to evaluate sites early. One is that high resolution mapping of the
sites for geologic sites and landing hazards requires the sharp-eyed cameras of
the Mars Reconnaissance orbiter. That
spacecraft reached Mars in 2006, and NASA wants to make maximum use of it while
it remains healthy and has an adequate fuel supply.

The mission’s engineers also want an early look at the most desirable
landing sites to determine whether the 2020 rover will need a significant
upgrade in its landing system. The
closest the mission’s operators currently can target the lander is to an ellipse
25 by 20 kilometers. A simple design
change can reduce that ellipse area by 40%.
Unfortunately, the richest sites for exploration often don’t have the
smooth surfaces needed to ensure a safe landing within their landing ellipses. The Curiosity rover, for example, will spend
more than two years getting from its safe landing site to the starting point
for its actual target area.
(Fortunately, there’s been great science along the way.)

For the 2020 mission, NASA would like to avoid another long road trip
at the start of the mission. If the
sites of greatest interest turn out to turn out to have hazards, then NASA will
consider a technology called Terrain Relative Navigation (TRN). With TRN, the landing system will compare
images taken during the final descent against a stored map of safe landing zones. It will then steer the landing to one of
those safe harbors. Without TRN, a mission
to the NE Syrtis Major site, for example, has an 87% chance of a safe landing;
with TRN the chance of safe landing increases to over 98%. However, the TRN technology would be
expensive to develop and test. NASA
wants to know that it is likely to be needed before committing to it for a
mission that’s already being done on a bargain budget.

The two meetings showed that despite an incredible run over the last couple of decades, for Mars the
best may still be to come.

Note: All the presentations promoting landing sites from the landing site workshop are available on-line. If
you’re not a geologist, you may want to read Emily Lakdawalla’s posts on Mars’ geologic
eras and on key
minerals that suggest past aqueous environments. Wikipedia also has articles on the Noachian era and its successor the Hesperian era during which
Mars’ surface transitioned from an impact ridden world, to one with possible
abundant surface water, and then progressively dried out. The 2020 mission is likely to focus on sites
that contain remnants from one or both of these eras (as the NE Syrtis Major
site does).

About Me

You can contact me at futureplanets1@gmail.com with any questions or comments.
I have followed planetary exploration since I opened my newspaper in 1976 and saw the first photo from the surface of Mars. The challenges of conceiving and designing planetary missions has always fascinated me. I don't have any formal tie to NASA or planetary exploration (although I use data from NASA's Earth science missions in my professional work as an ecologist).
Corrections and additions always welcome.